Positive shutoff valve



Patented Nov. 4, 1952 run A%- Taft, Ba uesviue,

liii's retreleuin' 'Gbm'liany,

were

ne sssi fioi men'- a corporation of Dela- As niesiias semester 15, iiii'iserisina. their '4' Glaiifis. (c1. 2-5"i'27) 1 This invention relates to elve Iii one ofjts more specific aspects it relates to valvesof the positive shut-off type for control of flow of fluid at high pressures of at very low pressures from either direction; I p I U In conventional v"-lvefs; o'r especially in valves for controlling O fih h pressure fluids or very low pressure fluids, fiew e; valves; if any,- a-re positive shut-'ofi ag. st fluid new from eitherdirection. I M An object of my invention is topiovide a valve which gives apositive s'eal-against-highpressure or against very low mass Another object of my invention is to providea valveoi a posi tive shut-off type which" test control the flow of high pressure or low "re fiu-ids in either direction. Anothefobjec In-y'invention ay be opened or is to provide" a valve which W v closed with a} very short distance of plunger travel. Y

These and other" objects those skilled in the art from: (ii of thef ol lowing disclosure taken ih c tion with the attached drawing which res'pectii'iely describes and illustrates one embodiment of me ii'ive'nt-ic'a'n.

The figure is a lbil'itlidifiilsectional view" of the valve of my inventidm V v v Referring now to thefdraiwi-iig my valveis 66in posed ofa valve body It through which win- Be reali ed by duit generally referred' toby meet his conduit I2 is composedof severa seet am ly sections I 3, I4, I5 F63 I l and 1 sectionsl3 and l8 are'provide'd w'ith i-hternal thread's for attaching to pipes.

In the figure avalve stem: 21- hes' oh' its hottoma plunger 26, which plunger trmineiteswith a compressive ring member 28; The up eren'd of the valve stem mas beshoulderedand thread ed to accommodate a valve'handlen and a nut 2 3. The valve stem and" plunger assembly is held in place in the valve body 16y a" gland nut member 24'. A- gasket 29 is placed between the gland nut 24 and the valve-body H' toprevent leakage of fluid-through the-"threadedsection I91- A resilient O-ring- 25in "groove'tfl in the' valve" stem 2| serves to sealthe annular.siiace between the valve stem 2| and the gland nut against leakage of fluid. A resilient: ,ring member 21; is? inserted between the; top of-the valve plunger 26 and the underside ZOpfthe gIand nut'Zfl so that the valve plunger will notiam against the-sur face when the valve-is full-y opened- A ring member 3| is placed uponla seatl38ggf the valve, The main portion-of the ring isheldj off theseat a sho'rt distance by the small raisedportion 6. The upper surface of the-3T has a plurality or radia gree'ves orchannels 31 to'fa'ssist the flow of 'fluid when the compression ring member 2315 raised only a slight extent,

Directly under the" compressive ring member 28 is an O -ring member 32; Th 'is Q-rin'g,'a1s well as the "-"-ri.n'g 2Z5, is made of a resilient material siieh' as rubber. ,l V v Inside this O-ring 32 isiinserted a hollow pin r'nem'loe'qi 3 3 The longitudinal axis of this hollow pinm ember coincides substantially with the axis of the valve stem 21. Theouter diameter of this 110110? is slightly s anertnm the inner an ei fi' ivi t o p s ne mem r 2 so tha the compression ringls may move downwardly around the upper end of the hollowpin without touching or binding and so th zitthctmprssive ringmember might be raised without lifting he i a .l i, Y The hol wpin 33' has bottom channels or grooves 35; The upper end of the hollow pin member is also provided with-grooves 3'9.

This hollow pin member rests in ahole extending from the bottom of the valve seat 33 downward some distance. The bottom of this hole iliis-connected with the'condu'it section l1 while the upper portion of this hole" 40 opens into the conduit section 1'5; H P

The va ve mange 2e is threaded to fit the in Side threads 41' of the glafl'dnut HQan d: it these threads-which cause the raising or lowering of the" valve plunger 2 6 u'ponrttsuori of the va ve handle 22. In one valve which I have ma e the threads M were rather fine threads} there being 16 threads to the inch." opening or clos such a valve with 16 threads to the inch at one-sixth of a' turn from an open position closes the valve or conversely from a closed; position, Opensth'e valve. When thevalve is inan open position, the resilient member 21' assists the O-ring 25 in'sealin'g the area around the valve stem" against leakage of fluids When the-Valve is closed; the'O-ring 25' assumes this entire sealing load and I have found'that with a well fitted Owing-'25 this one-"ring makes an efficient' seal.

When-the valve isop'end and fluid is flowing from left to ,rightyfl-uid enters the valve" body through conduit member. f8; passes through con du'it member ["1 and passes throughthe grooves 35" of the; hollow pin 33' into the eenter conduit section 16 and thence into the conduit section I5 directly under theqvalve plunger 25; From the conduit section I5 the fluid then passes'under the compressive ringmeinber ZBfaIld'IIOWaId" the right tion l3.

When fluid flows from right to left it passes from conduit section I3 through channel l4 on top of the collar member 3| under the compressive ring 28, through space I5 and grooves 39 into the vertical channel I6 of the pin 33, then through the grooves 35 of the pin and through the channel I! into the outlet section I8.

When the valve plunger 26 is lowered toward its closed position, the bottom surface of the compressive ring member 28 approaches the O-ring member 32. When high pressure gas is flowing in either direction, as the valve plunger 26 approaches the O-ring member 32, this member is deformed in a downstream direction and the valve becomes closed. When low pressure gas is flowing in either direction, the valve plunger touches and very slightly deforms the O-ring to initiate its deformation and effect the seal.

When the valve is closed, the greater the pressure drop across the seal the tighter is the seal against the flow of fluid from either direction. In explanation of this point, high fluid pressure from conduit section l8, for example, is transmitted through conduit section I! and through section l6, into the conduit section I5. Under these conditions, of course pressure on the downstream side r in conduit sections I3 and I4 is lower than the pressure on the upstream side and the O-ring 32 is further deformed from its high pressure side toward its low pressure side to make a completely fluid tight seal between the O-ring member 32, the valve seat 38, the ring member 3|, and the bottom surface of the compressive ring member 28. In this manner fluid tending to flow from the left to right is completely closed off.

Pressure is also placed upon the lower portion of ring 32 due to the communication of conduit I! with the interspace at 40 between annular member 33 and the valve body, this interspace, in turn, communicating with the lower portion of the ring 32. As a result, the ring 32 is stressed and assumes an elliptical shape so as to seal the region at 32 between the ring and annular member 3| as well as the region between the flange 28 and annular member 3|. The upward pressure exerted on the ring through the interspace 40 and the downward pressure exerted thereon through the region I5 are so balanced that there is no tendency for the ring to move upwardly or jam as the plunger 26 is raised to open the valve.

When fluid is flowing from conduit section I3 toward conduit section I8, or from right to left and the valve 26 is closed, then the O-ring 32 is pushed tightly against the valve seat 38, against the outer surface of the hollow pin member 33 and against the under surface of the compressive ring member 28 to make the seal against flow of fluid. This sealing pressure consists of a component directed downwardly against the ring through the passage at 38 between the annular member 3| and the valve body. The resultant pressure causes the ring 32 to assume an elliptical configuration and seal the region between annular member 33, the valve seat body as well as the region between annular member 33 and the flange 28. As before, the pressure components are so balanced that there is no tendency for the ring to move upwardly or jam as the plunger 26 is raised to open the valve.

I have found that in addition to sealing of! completely the flow of fluid from either direction, that upon opening the valve slightly any relative amount of fluid may be permitted to flow 4 in either direction. In other words, in addition to being a positive shut-01f valve, my valve also is a rate of flow control valve. I have used this valve in services up to 600 pounds per square inch pressure and under such pressure conditions when the valve was closed sealing was complete from either left to right or from right to left. The flow of small quantities of fluid was easily controlled by partly closing the valve. My valve may be used for pressures as high as 4,000 pounds, or higher, per square inch or for pressures considerably lower than atmospheric.

It will be obvious to those skilled in the art that various relative dimensions may be changed as desired and to fit particular problems. For example, a smaller or larger number of threads per inch may be used at threads 4I so that the distance of travel of the valve plunger will be greater or less per revolution of the valve handle. Thus, a valve equipped with large threads at 4| will permit flow of larger volumes of fluid per turn of the valve handle than a valve made with low pitch threads.

The size of the conduit section II and of the conduit section I4 also effects the flow of fluid under wide open conditions of valve setting. Similarly the size of the opening I6 in the hollow pin member and the size and number of slots 35 and 39 in the pin member 33, effect the flow of fluid. Larger slots, of course, make for a larger capacity valve.

The valve described in detail herein is a straight valve, but the principles I have disclosed may be applied to a right angle or valve as another embodiment. In such a valve, conduits I3, I4, I5 and I6 are similar to those of the figure. The left hand portion of the valve body with its conduit sections I8 and I1 is replaced by a valve body portion extending downward, the axis of which coincides and is an extension of the axis of the valve stem 2| and channel I6. The pin member 33 with its channelled top and bottom may be the same as shown in the drawing. A small vertically disposed channel extends downward from the bottom of conduit section I6 and this channel opens into a larger diameter threaded section corresponding to conduit section I8. A valve of this 90 type operates in exactly the same manner as the straight or valve.

My valve finds special utility in laboratory apparatus where very high fluid pressures, of the order of several thousand pounds per square inch, are encountered. Fluids under such pressures may be entirely closed off from either direction or the flow controlled from either direction.

Materials of construction may for the most part be selected from among those commercially available. The valve body member II may be made from cast iron or steel, either ordinary carbon steel or stainless steel as desired. The gland nut member 24may also be made of any material. This gland nut member 24 should preferably be made with its exterior portion hexagonal in shape, for example, so that it may be tightened or loosened from the valve body with a wrench. The valve'stem 2| may be made of rod stock with the valve plunger 21 fastened thereto in any manner desired, for example, the lower end of the valve stem may be threaded and screwed into the plunger and'keyed or pinned thereto to prevent separation of the two, or the valve stem-plunger may be turned as an integral unit from a piece of larger diameter stock.

Having disclosed my invention, I claim:

1. A high-pressure fluid shut-off valve comprising, in combination, a valve body having a conduit therethrough, a valve seat in said conduit, an annular resilient packing washer of circular cross-section engaging said seat, a valve head movably mounted in said body disposed in said movement to force said washer against said seat and thereby control the flow of high pressure fluid through said conduit, and inner and outer retaining rings concentrically disposed relative to said washer, said rings being provided with a passage from the interior to exterior thereof adjacent each end thereof, each of said passages being disposed to pass said pressure fluid at all times but said rings being disposed to back-up said washer centrally in the direction of fluid pressure drop.

2. A high-pressure fluid shut-ofi valve comprising, in combination, a valve body having a conduit therethrough, a valve seat in said conduit, an annular resilient packing washer disposed to engage said seat, a valve head movably mounted in said body disposed in said movement to force said washer against said seat and thereby control the flow of high pressure fluid through said conduit, and inner and outer retaining rings concentrically disposed relative to said washer, said rings being provided with an opening from the interior to the exterior thereof adjacent each end thereof, each of said rings being disposed to pass said pressure fluid at both sides of said washer at all times but to back-up said washer centrally in the direction of fluid pressure drop.

3. A high pressure fluid shut-off valve comprising, in combination, a valve body having a conduit therethrough, a valve seat in said conduit, an annular resilient packing washer of circular cross-section disposed to engage said seat, a valve head movably mounted in said body disposed in said movement to force said washer against said seat and thereby control the flow of high pressure fluid through said conduit, and inner and outer retaining rings concentrically disposed relative to said washer, said rings being disposed to pass said pressure fluid at both sides of said washer at all times but to back-up said washer centrally in the direction of fluid pressure drop.

4. A high-pressure fluid shut-01f valve comprising, in combination, a valve body havin a conduit therethrough, a valve seat in said conduit, an annular resilient packing washer disposed to engage said seat, a valve head movably mounted in said body disposed in said movement to force said washer against said seat and thereby control the flow of high pressure fluid through said conduit, and inner and outer retaining rings concentrically disposed relative to said washer, said rings being disposed to pass said pressure fluid at both sides of said washer at all times but to back-up said washer centrally in the direction of fluid pressure drop.

TOM A. TAR-R.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 449,161 Lacy Mar. 31, 1891 717,990 Harvey Jan. 6, 1903 1,372,244 Paske Mar. 22, 1921 1,667,580 Albrecht Apr. 24, 1928 2,136,835 Begg Nov. 15, 1938 2,252,923 Granetz Aug. 19, 1941 FOREIGN PATENTS Number Country Date 12,911 Great Britain of 1904 

